Apparatus for grinding balls.



No. 643,696. Patefited Feb. 20, I900. F. w. TAYLOR.

APPARATUS FOR GRINDING BALLS. (Application filed Apr. 28, 1898.) (No Model.)

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FREDERICK W. TAYLOR, OF PHILADELPHIA, PENNSYLVANIA.

APPARATUS FOR GRINDING BALLS.

PECIFIGATION forming part of Letters Patent No. 643,696, dated February 20, 1906.

Application filed April 28,

T0 to whom it may concern:

Be it known that I, FREDERICK W. TAYLOR, of Philadelphia, (Germantowm) county of Philadelphia,and State of Pennsylvania, have invented an Improvement in Apparatus for Grinding Balls, of which the following description, in connection withthe accompanying drawings, is a specification, like letters on the drawings representing like parts.

The present invention relates to an apparatus for grinding metallic balls, such as the steel balls which are now commonly used in bearings.

In carrying out the invention a quantity of balls in a compact mass are caused to eddy or flow, so to speak, there being substantially-constant interchange of position of balls in the different parts of the mass, so that every ball moves in frictional contact with the neighboring balls, each ball being therefore subjected to the grinding operation, which operation is enhanced by causing a grinding mixture, such as oil and emery, to permeate the mass during the flow of the balls. The

said flow is produced by confining the massof balls between stationary and movable members, the movable member preferably having a high velocity, it being obvious therefore that the balls in immediate contact with the movable member will tend to travel there with and to carry the adjacent balls along with them, while the balls in immediate contact with the stationary member are retarded. There is also a tendency for the balls to move away from the movable member, the balls which move away being replaced by others, there being therefore a continual interchange of position or eddying of the balls in the mass, and while at any given moment the different balls may move with different velocities and travel one past another with grinding action the average and aggregate movement of each ball through the mass will approximately equal that of every other ball. The balls, being spherical and being urged forward by an impetus at one side and impeded by engagement with other balls at the opposite side, will rotate or turn so that every part of each ball will come in contact with other balls, thus insuring an even and regular grinding awayof the surface.

The apparatus embodying the invention comprises, essentially, a receptacle or pot which is adapted to contain the mass of balls and the grinding mixture and a confining portion between which and the walls of the pot the balls are confined. One of the members thus described is provided with means for causing it to travel or rotate with relation to the other, the pot being preferably stationary and the confining member provided with a rotatable shaft. The said members may be constructed and arranged in any suitable or usual way and may be provided, respectively, with projections or abutments to further accelerate the flow of the balls adjacent to the movable member and impede the flow of the balls adjacent to the stationary member.

The invention further relates to certain de tails of construction and arrangement, which will be hereinafter described.

Figure 1 is a vertical section of an apparatus embodying the invention; and Fig. 2, a sectional side elevation of the top portion thereof looking toward the right, Fig. 1. Fig. 3 is a plan view of the lower face of the wearing-piece b and Fig. 4 a section on line 4 4 of Fig. 3.

The pot or receptacle a is herein shown as the stationary member and is adapted to contain a mass of balls, which are confined therein by the traveling member 19, which is shown as secured to the shaft b arranged to be rotated by gears 17 and b to set up a current or flow of balls, as hereinbefore described. The said member I), as shown, is of substantially the same general shape as that of the interior of the member a, so that the mass of balls is substantially uniform throughout, such construction, however, not being essential, it being practicable, forexample, to arrange one of the parts eccentric to the other to add a stirring or kneading action to the flowing action.

To aid in retarding the balls which lie along the surface of the stationary member a, the said member is shown as provided with ribs or projections a projecting into the mass, and the member I) is of a somewhat-irregular shape or configuration The only part of the apparatus where any accuracy in fit or relative position of the parts is required is the part along the upper portion of the members where the two are contiguous and must approximately fit to conline the balls, and to take up the wear at this part and increase the life of the apparatus the member a is herein shown as provided with an annular lining-ring (1 which is held in position by cap screws or bolts a the said ring lying adjacent to the upper portion of the member I) and extending somewhat below the same. The said member I) is provided with a similar removable wearing-piece N, which is shown as secured thereto by means of a ring Z) and screws or bolts The remaining portions of the members are capable of effectual operation until completely worn out, so that by occasionally removing the wearing-rings the apparatus may be kept in operation for a long time.

To increase the eddying or flowing tendency of the balls, a portion of the member 7) (herein shown as the wearing-ring b is provided with a cam-surface, as b 12 the action of which is to force the mass of balls down along the sides of the member a as the member 11 rotates. The said wearing-ring b is also shown as provided with a flange Z7 extending downward along the wearing-piece (1. and protecting a portion thereof from direct contact with the balls.

To prevent the grinding mixture from escaping through the agency of centrifugal force due to the rapid rotation of the member Z), the walls of the pot a are shown as extended upward at (0 and an annular shell 0 is secured to a sleeve 0 which surrounds the shaft N, there being an annular space between the walls of the pot and the said shell in which the grinding mixture can rise without being driven out. The said shell 0 is shown as connected, as by a chain 0 with a weight 0, the chain passing over a pulley 0 so that the weight acts as a counterpoise when the member I) is to be lifted away from the member a to remove the balls which have been ground and put in others which are to be ground.

The shaft 11 is capable of rotation within the sleeve 0 but is longitudinally confined with relation thereto by means of flanges D and b the latter being shown as threaded on the shaft and removable therefrom. The said shaft is also shown as connected with the gear Z) by a spline connection to admit of the longitudinal movement thereof,as above described.

The part a is shown as provided with an outlet-opening and plug ct for the purpose of drawing off the oil or grinding mixture when it is necessary to do so.

\Vhile it is not essential to the successful operation of grinding balls in accordance with the herein-described method, it is desirable to subject the mass of balls to greater or less pressure,it having been found, in fact,that as much pressure as is consistent with the rapid movement of the member I) is beneficial. To

produce such pressure, therefore, the shaft 12 is acted upon by a weight b, Fig. 2, the tendency of which is to press the member I) downward toward the walls of the pot a. The said weight is hung on a lever b shown as pivoted on a stud D supported on an arm or standard 5 said stud being capable of turning in said arm. The said lever normally rests on a support I), which has a bearing at the end of the shaft, Fig. 2, so that the weight exerts a downward pressure on said shaft. When, however, the shaft is to be lifted, the lever may be swung to one side and rested on the support I).

It is impossible to observe the exact movement of the balls while undergoing the grinding operation; but it has been found as the result of the actual use of the herein-described grinding apparatus that after a short period of operation of the machine-say, for example, fifteen minutes-all of the balls have been subjected to substantially the same amount of grinding action, having been reduced an equal amount from their original size, and that each ball has been acted upon substantially uniformly over its entire surface, the tendency being, however, to grind away the more prominentparts of the surface, if there be any, more than less prominent parts, or, in other words, to give a closer approximation to true sphericity at the end of the grinding operation than at the beginning. It can thus be determined by a trial how long a time is required under determinate conditions of speed and pressure to reduce the balls a given amount-say, one one-thousandth of an inch in diameterand consequently how long the operation is to be continued to reduce them whatever amount may be desired as the result of the grinding operation. It has been found, furthermore, that the form of the grinding members can be varied widely, it being essential only that there should be a substantially-continuous interchange of position of the balls throughout the mass, so that every ball is subjected to substantially the same action and to the same degree as all of the others. The form shown is therefore merely intended as an illustration of one of a number of forms that might be used, being one that has proved to be efficient in actual practice.

It is probable that the conical or tapering form of the grinding members shown tends to produce a travel or eddying circulation of the balls up and down the inclined surfaces, the balls traveling along the surface of one member from the apex toward the base and along the other member from the base toward the apex, while there is probably more or less interchange of position or traveling of the balls from the surface of one toward the surface of the opposite member, to be replaced by other balls traveling between the said members in the reverse direction at all points in the space between the two grinding members.

The outer member or pot is shown as having at its lower end or apex a reentering surface projecting toward the apex of the inner member in order to enhance the movement or a ases s interchange of position of the balls at this point or to prevent possibility of a portion of the balls lagging or becoming stagnant in the apex of the outer member and thus receiving less of the grinding action than others.

The ribs or cams on the grinding-surfaces herein shown are not essential, as efficient and uniform grinding can be done in a machine like that shown with the surfaces of the grinding members substantially smooth. The grinding action is probably due mainly to the frictional movement of each ball with relation to its neighbors, although a considerable.

portion of the grinding operation may be derived directly from the frictional engagement of the grinding members with the balls that are at any moment in contact therewith and which are called the grinding members, as their relative movement produces the entire movement of the balls with relation each to the others throughout the mass, by which the grinding is effected.

I claim- 1. An apparatus for grinding balls which consists of a receptacle or pot to contain a mass of balls, a confining member to closely confine said ballsin the receptacle, and means for producing a movement of one of said parts relative to the other, substantially as described.

2. An apparatus for grinding balls comprising a stationary pot or receptacle adapted to contain a mass of balls and a grinding mixture, and a movable confining member adapted to closely confine the mass of balls in said pot and to set the mass in motion, substantially as described.

3. An apparatus for grinding balls comprising stationary and movable members arranged to confine a mass of balls in the space between them, and a cam portion or surface on one of said members projecting into the space occupied by the balls, substantially as described.

4. An apparatus for grinding balls comprising a pot or receptacle to contain a. mass of balls, a tapered confining member projecting into said receptacle, and means for producing rotation of said confining member, substantially as described.

5. An apparatus for grinding balls comprising a receptacle to contain a mass of balls and constituting one grinding member; a confining portion to confine the said mass of balls within said receptacle and constituting the other grinding member; means for producing a movement of one of said members With relation to the other; and contiguous movable portions connected with said members respectively, substantially as described.

6. An apparatus for grinding balls comprising a receptacle to contain a mass of balls and constituting one grinding member, aconfining portion to confine the said mass of balls within said receptacle and constituting the other grinding member; means for pro ducing a movement of one of said members with relation to the other; and flanges, pro

jecting from said members respectively,

along the contiguous portions thereof, substantially as and for the purpose described. In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

FREDERICK XV. TAYLOR. Witnesses:

H. J. LIVERMORE, NANCY P. FORD. 

